How is molybdenum recovered as a by-product of copper mining?

Molybdenum is frequently recovered as a by-product from complex copper-molybdenum porphyry deposits, which account for approximately 60 percent of global molybdenum production.1

The recovery process begins after the ore is extracted via open-pit or underground mining methods. Once the ore has been crushed and ground, the metallic minerals are separated from the gangue minerals—and the molybdenum and copper are separated from each other—using flotation processes. These processes utilize a wide variety of reagents to isolate the minerals.2

The resulting molybdenum concentrates typically contain between 85 and 92 percent molybdenum disulfide ($Mo{S}_2$) and less than 0.5 percent copper. Following this separation, the concentrate is generally converted into technical molybdic oxide ($Mo{O}_3$) through roasting in multiple-hearth furnaces to reach its commercial form.23